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|
/*
* Copyright (c) 1993, 1995 Jan-Simon Pendry
* Copyright (c) 1993, 1995
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)procfs_vnops.c 8.18 (Berkeley) 5/21/95
*
* $FreeBSD$
*/
/*
* procfs vnode interface
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/fcntl.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <sys/vnode.h>
#include <sys/uio.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/dirent.h>
#include <sys/malloc.h>
#include <machine/reg.h>
#include <vm/vm_zone.h>
#include <miscfs/procfs/procfs.h>
#include <sys/pioctl.h>
static int procfs_access __P((struct vop_access_args *));
static int procfs_badop __P((void));
static int procfs_bmap __P((struct vop_bmap_args *));
static int procfs_close __P((struct vop_close_args *));
static int procfs_getattr __P((struct vop_getattr_args *));
static int procfs_ioctl __P((struct vop_ioctl_args *));
static int procfs_lookup __P((struct vop_lookup_args *));
static int procfs_open __P((struct vop_open_args *));
static int procfs_print __P((struct vop_print_args *));
static int procfs_readdir __P((struct vop_readdir_args *));
static int procfs_readlink __P((struct vop_readlink_args *));
static int procfs_reclaim __P((struct vop_reclaim_args *));
static int procfs_setattr __P((struct vop_setattr_args *));
/*
* This is a list of the valid names in the
* process-specific sub-directories. It is
* used in procfs_lookup and procfs_readdir
*/
static struct proc_target {
u_char pt_type;
u_char pt_namlen;
char *pt_name;
pfstype pt_pfstype;
int (*pt_valid) __P((struct proc *p));
} proc_targets[] = {
#define N(s) sizeof(s)-1, s
/* name type validp */
{ DT_DIR, N("."), Pproc, NULL },
{ DT_DIR, N(".."), Proot, NULL },
{ DT_REG, N("mem"), Pmem, NULL },
{ DT_REG, N("regs"), Pregs, procfs_validregs },
{ DT_REG, N("fpregs"), Pfpregs, procfs_validfpregs },
{ DT_REG, N("dbregs"), Pdbregs, procfs_validdbregs },
{ DT_REG, N("ctl"), Pctl, NULL },
{ DT_REG, N("status"), Pstatus, NULL },
{ DT_REG, N("note"), Pnote, NULL },
{ DT_REG, N("notepg"), Pnotepg, NULL },
{ DT_REG, N("map"), Pmap, procfs_validmap },
{ DT_REG, N("etype"), Ptype, procfs_validtype },
{ DT_REG, N("cmdline"), Pcmdline, NULL },
{ DT_REG, N("rlimit"), Prlimit, NULL },
{ DT_LNK, N("file"), Pfile, NULL },
#undef N
};
static const int nproc_targets = sizeof(proc_targets) / sizeof(proc_targets[0]);
static pid_t atopid __P((const char *, u_int));
/*
* set things up for doing i/o on
* the pfsnode (vp). (vp) is locked
* on entry, and should be left locked
* on exit.
*
* for procfs we don't need to do anything
* in particular for i/o. all that is done
* is to support exclusive open on process
* memory images.
*/
static int
procfs_open(ap)
struct vop_open_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct pfsnode *pfs = VTOPFS(ap->a_vp);
struct proc *p1, *p2;
p2 = PFIND(pfs->pfs_pid);
if (p2 == NULL)
return (ENOENT);
if (pfs->pfs_pid && p_can(ap->a_p, p2, P_CAN_SEE, NULL))
return (ENOENT);
switch (pfs->pfs_type) {
case Pmem:
if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) ||
((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE)))
return (EBUSY);
p1 = ap->a_p;
if (p_can(p1, p2, P_CAN_DEBUG, NULL) &&
!procfs_kmemaccess(p1))
return (EPERM);
if (ap->a_mode & FWRITE)
pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL);
return (0);
default:
break;
}
return (0);
}
/*
* close the pfsnode (vp) after doing i/o.
* (vp) is not locked on entry or exit.
*
* nothing to do for procfs other than undo
* any exclusive open flag (see _open above).
*/
static int
procfs_close(ap)
struct vop_close_args /* {
struct vnode *a_vp;
int a_fflag;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct pfsnode *pfs = VTOPFS(ap->a_vp);
struct proc *p;
switch (pfs->pfs_type) {
case Pmem:
if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL))
pfs->pfs_flags &= ~(FWRITE|O_EXCL);
/*
* If this is the last close, then it checks to see if
* the target process has PF_LINGER set in p_pfsflags,
* if this is *not* the case, then the process' stop flags
* are cleared, and the process is woken up. This is
* to help prevent the case where a process has been
* told to stop on an event, but then the requesting process
* has gone away or forgotten about it.
*/
if ((ap->a_vp->v_usecount < 2)
&& (p = pfind(pfs->pfs_pid))
&& !(p->p_pfsflags & PF_LINGER)) {
p->p_stops = 0;
p->p_step = 0;
wakeup(&p->p_step);
}
break;
default:
break;
}
return (0);
}
/*
* do an ioctl operation on a pfsnode (vp).
* (vp) is not locked on entry or exit.
*/
static int
procfs_ioctl(ap)
struct vop_ioctl_args *ap;
{
struct pfsnode *pfs = VTOPFS(ap->a_vp);
struct proc *procp, *p;
int error;
int signo;
struct procfs_status *psp;
unsigned char flags;
p = ap->a_p;
procp = pfind(pfs->pfs_pid);
if (procp == NULL) {
return ENOTTY;
}
if ((error = p_can(p, procp, P_CAN_DEBUG, NULL)))
return (error == ESRCH ? ENOENT : error);
switch (ap->a_command) {
case PIOCBIS:
procp->p_stops |= *(unsigned int*)ap->a_data;
break;
case PIOCBIC:
procp->p_stops &= ~*(unsigned int*)ap->a_data;
break;
case PIOCSFL:
/*
* NFLAGS is "non-suser_xxx flags" -- currently, only
* PFS_ISUGID ("ignore set u/g id");
*/
#define NFLAGS (PF_ISUGID)
flags = (unsigned char)*(unsigned int*)ap->a_data;
if (flags & NFLAGS && (error = suser(p)))
return error;
procp->p_pfsflags = flags;
break;
case PIOCGFL:
*(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags;
case PIOCSTATUS:
psp = (struct procfs_status *)ap->a_data;
psp->state = (procp->p_step == 0);
psp->flags = procp->p_pfsflags;
psp->events = procp->p_stops;
if (procp->p_step) {
psp->why = procp->p_stype;
psp->val = procp->p_xstat;
} else {
psp->why = psp->val = 0; /* Not defined values */
}
break;
case PIOCWAIT:
psp = (struct procfs_status *)ap->a_data;
if (procp->p_step == 0) {
error = tsleep(&procp->p_stype, PWAIT | PCATCH, "piocwait", 0);
if (error)
return error;
}
psp->state = 1; /* It stopped */
psp->flags = procp->p_pfsflags;
psp->events = procp->p_stops;
psp->why = procp->p_stype; /* why it stopped */
psp->val = procp->p_xstat; /* any extra info */
break;
case PIOCCONT: /* Restart a proc */
if (procp->p_step == 0)
return EINVAL; /* Can only start a stopped process */
if ((signo = *(int*)ap->a_data) != 0) {
if (signo >= NSIG || signo <= 0)
return EINVAL;
psignal(procp, signo);
}
procp->p_step = 0;
wakeup(&procp->p_step);
break;
default:
return (ENOTTY);
}
return 0;
}
/*
* do block mapping for pfsnode (vp).
* since we don't use the buffer cache
* for procfs this function should never
* be called. in any case, it's not clear
* what part of the kernel ever makes use
* of this function. for sanity, this is the
* usual no-op bmap, although returning
* (EIO) would be a reasonable alternative.
*/
static int
procfs_bmap(ap)
struct vop_bmap_args /* {
struct vnode *a_vp;
daddr_t a_bn;
struct vnode **a_vpp;
daddr_t *a_bnp;
int *a_runp;
} */ *ap;
{
if (ap->a_vpp != NULL)
*ap->a_vpp = ap->a_vp;
if (ap->a_bnp != NULL)
*ap->a_bnp = ap->a_bn;
if (ap->a_runp != NULL)
*ap->a_runp = 0;
return (0);
}
/*
* _reclaim is called when getnewvnode()
* wants to make use of an entry on the vnode
* free list. at this time the filesystem needs
* to free any private data and remove the node
* from any private lists.
*/
static int
procfs_reclaim(ap)
struct vop_reclaim_args /* {
struct vnode *a_vp;
} */ *ap;
{
return (procfs_freevp(ap->a_vp));
}
/*
* _print is used for debugging.
* just print a readable description
* of (vp).
*/
static int
procfs_print(ap)
struct vop_print_args /* {
struct vnode *a_vp;
} */ *ap;
{
struct pfsnode *pfs = VTOPFS(ap->a_vp);
printf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n",
pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags);
return (0);
}
/*
* generic entry point for unsupported operations
*/
static int
procfs_badop()
{
return (EIO);
}
/*
* Invent attributes for pfsnode (vp) and store
* them in (vap).
* Directories lengths are returned as zero since
* any real length would require the genuine size
* to be computed, and nothing cares anyway.
*
* this is relatively minimal for procfs.
*/
static int
procfs_getattr(ap)
struct vop_getattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct pfsnode *pfs = VTOPFS(ap->a_vp);
struct vattr *vap = ap->a_vap;
struct proc *procp;
int error;
/*
* First make sure that the process and its credentials
* still exist.
*/
switch (pfs->pfs_type) {
case Proot:
case Pcurproc:
procp = 0;
break;
default:
procp = PFIND(pfs->pfs_pid);
if (procp == 0 || procp->p_cred == NULL ||
procp->p_ucred == NULL)
return (ENOENT);
if (p_can(ap->a_p, procp, P_CAN_SEE, NULL))
return (ENOENT);
}
error = 0;
/* start by zeroing out the attributes */
VATTR_NULL(vap);
/* next do all the common fields */
vap->va_type = ap->a_vp->v_type;
vap->va_mode = pfs->pfs_mode;
vap->va_fileid = pfs->pfs_fileno;
vap->va_flags = 0;
vap->va_blocksize = PAGE_SIZE;
vap->va_bytes = vap->va_size = 0;
vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0];
/*
* Make all times be current TOD.
* It would be possible to get the process start
* time from the p_stat structure, but there's
* no "file creation" time stamp anyway, and the
* p_stat structure is not addressible if u. gets
* swapped out for that process.
*/
nanotime(&vap->va_ctime);
vap->va_atime = vap->va_mtime = vap->va_ctime;
/*
* If the process has exercised some setuid or setgid
* privilege, then rip away read/write permission so
* that only root can gain access.
*/
switch (pfs->pfs_type) {
case Pctl:
case Pregs:
case Pfpregs:
case Pdbregs:
if (procp->p_flag & P_SUGID)
vap->va_mode &= ~((VREAD|VWRITE)|
((VREAD|VWRITE)>>3)|
((VREAD|VWRITE)>>6));
break;
case Pmem:
/* Retain group kmem readablity. */
if (procp->p_flag & P_SUGID)
vap->va_mode &= ~(VREAD|VWRITE);
break;
default:
break;
}
/*
* now do the object specific fields
*
* The size could be set from struct reg, but it's hardly
* worth the trouble, and it puts some (potentially) machine
* dependent data into this machine-independent code. If it
* becomes important then this function should break out into
* a per-file stat function in the corresponding .c file.
*/
vap->va_nlink = 1;
if (procp) {
vap->va_uid = procp->p_ucred->cr_uid;
vap->va_gid = procp->p_ucred->cr_gid;
}
switch (pfs->pfs_type) {
case Proot:
/*
* Set nlink to 1 to tell fts(3) we don't actually know.
*/
vap->va_nlink = 1;
vap->va_uid = 0;
vap->va_gid = 0;
vap->va_size = vap->va_bytes = DEV_BSIZE;
break;
case Pcurproc: {
char buf[16]; /* should be enough */
vap->va_uid = 0;
vap->va_gid = 0;
vap->va_size = vap->va_bytes =
snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid);
break;
}
case Pproc:
vap->va_nlink = nproc_targets;
vap->va_size = vap->va_bytes = DEV_BSIZE;
break;
case Pfile: {
char *fullpath, *freepath;
error = textvp_fullpath(procp, &fullpath, &freepath);
if (error == 0) {
vap->va_size = strlen(fullpath);
free(freepath, M_TEMP);
} else {
vap->va_size = sizeof("unknown") - 1;
error = 0;
}
vap->va_bytes = vap->va_size;
break;
}
case Pmem:
/*
* If we denied owner access earlier, then we have to
* change the owner to root - otherwise 'ps' and friends
* will break even though they are setgid kmem. *SIGH*
*/
if (procp->p_flag & P_SUGID)
vap->va_uid = 0;
else
vap->va_uid = procp->p_ucred->cr_uid;
vap->va_gid = KMEM_GROUP;
break;
case Pregs:
vap->va_bytes = vap->va_size = sizeof(struct reg);
break;
case Pfpregs:
vap->va_bytes = vap->va_size = sizeof(struct fpreg);
break;
case Pdbregs:
vap->va_bytes = vap->va_size = sizeof(struct dbreg);
break;
case Ptype:
case Pmap:
case Pctl:
case Pstatus:
case Pnote:
case Pnotepg:
case Pcmdline:
case Prlimit:
break;
default:
panic("procfs_getattr");
}
return (error);
}
static int
procfs_setattr(ap)
struct vop_setattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
if (ap->a_vap->va_flags != VNOVAL)
return (EOPNOTSUPP);
/*
* just fake out attribute setting
* it's not good to generate an error
* return, otherwise things like creat()
* will fail when they try to set the
* file length to 0. worse, this means
* that echo $note > /proc/$pid/note will fail.
*/
return (0);
}
/*
* implement access checking.
*
* actually, the check for super-user is slightly
* broken since it will allow read access to write-only
* objects. this doesn't cause any particular trouble
* but does mean that the i/o entry points need to check
* that the operation really does make sense.
*/
static int
procfs_access(ap)
struct vop_access_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct pfsnode *pfs = VTOPFS(ap->a_vp);
struct vnode *vp = ap->a_vp;
struct proc *procp;
struct vattr *vap;
struct vattr vattr;
int error;
switch (pfs->pfs_type) {
case Proot:
case Pcurproc:
break;
default:
procp = PFIND(pfs->pfs_pid);
if (procp == NULL)
return (ENOENT);
if (p_can(ap->a_p, procp, P_CAN_SEE, NULL))
return (ENOENT);
}
vap = &vattr;
error = VOP_GETATTR(vp, vap, ap->a_cred, ap->a_p);
if (error)
return (error);
return (vaccess(vp->v_type, vap->va_mode, vap->va_uid, vap->va_gid,
ap->a_mode, ap->a_cred, NULL));
}
/*
* lookup. this is incredibly complicated in the
* general case, however for most pseudo-filesystems
* very little needs to be done.
*
* unless you want to get a migraine, just make sure your
* filesystem doesn't do any locking of its own. otherwise
* read and inwardly digest ufs_lookup().
*/
static int
procfs_lookup(ap)
struct vop_lookup_args /* {
struct vnode * a_dvp;
struct vnode ** a_vpp;
struct componentname * a_cnp;
} */ *ap;
{
struct componentname *cnp = ap->a_cnp;
struct vnode **vpp = ap->a_vpp;
struct vnode *dvp = ap->a_dvp;
char *pname = cnp->cn_nameptr;
struct proc *curp = cnp->cn_proc;
struct proc_target *pt;
pid_t pid;
struct pfsnode *pfs;
struct proc *p;
int i;
*vpp = NULL;
if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME ||
cnp->cn_nameiop == CREATE)
return (EROFS);
if (cnp->cn_namelen == 1 && *pname == '.') {
*vpp = dvp;
VREF(dvp);
/* vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, curp); */
return (0);
}
pfs = VTOPFS(dvp);
switch (pfs->pfs_type) {
case Proot:
if (cnp->cn_flags & ISDOTDOT)
return (EIO);
if (CNEQ(cnp, "curproc", 7))
return (procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc));
pid = atopid(pname, cnp->cn_namelen);
if (pid == NO_PID)
break;
p = PFIND(pid);
if (p == 0)
break;
if (p_can(curp, p, P_CAN_SEE, NULL))
break;
return (procfs_allocvp(dvp->v_mount, vpp, pid, Pproc));
case Pproc:
if (cnp->cn_flags & ISDOTDOT)
return (procfs_root(dvp->v_mount, vpp));
p = PFIND(pfs->pfs_pid);
if (p == 0)
break;
for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) {
if (cnp->cn_namelen == pt->pt_namlen &&
bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 &&
(pt->pt_valid == NULL || (*pt->pt_valid)(p)))
goto found;
}
break;
found:
return (procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid,
pt->pt_pfstype));
default:
return (ENOTDIR);
}
return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS);
}
/*
* Does this process have a text file?
*/
int
procfs_validfile(p)
struct proc *p;
{
return (procfs_findtextvp(p) != NULLVP);
}
/*
* readdir() returns directory entries from pfsnode (vp).
*
* We generate just one directory entry at a time, as it would probably
* not pay off to buffer several entries locally to save uiomove calls.
*/
static int
procfs_readdir(ap)
struct vop_readdir_args /* {
struct vnode *a_vp;
struct uio *a_uio;
struct ucred *a_cred;
int *a_eofflag;
int *a_ncookies;
u_long **a_cookies;
} */ *ap;
{
struct uio *uio = ap->a_uio;
struct dirent d;
struct dirent *dp = &d;
struct pfsnode *pfs;
int count, error, i, off;
static u_int delen;
if (!delen) {
d.d_namlen = PROCFS_NAMELEN;
delen = GENERIC_DIRSIZ(&d);
}
pfs = VTOPFS(ap->a_vp);
off = (int)uio->uio_offset;
if (off != uio->uio_offset || off < 0 ||
off % delen != 0 || uio->uio_resid < delen)
return (EINVAL);
error = 0;
count = 0;
i = off / delen;
switch (pfs->pfs_type) {
/*
* this is for the process-specific sub-directories.
* all that is needed to is copy out all the entries
* from the procent[] table (top of this file).
*/
case Pproc: {
struct proc *p;
struct proc_target *pt;
p = PFIND(pfs->pfs_pid);
if (p == NULL)
break;
if (p_can(curproc, p, P_CAN_SEE, NULL))
break;
for (pt = &proc_targets[i];
uio->uio_resid >= delen && i < nproc_targets; pt++, i++) {
if (pt->pt_valid && (*pt->pt_valid)(p) == 0)
continue;
dp->d_reclen = delen;
dp->d_fileno = PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype);
dp->d_namlen = pt->pt_namlen;
bcopy(pt->pt_name, dp->d_name, pt->pt_namlen + 1);
dp->d_type = pt->pt_type;
if ((error = uiomove((caddr_t)dp, delen, uio)) != 0)
break;
}
break;
}
/*
* this is for the root of the procfs filesystem
* what is needed is a special entry for "curproc"
* followed by an entry for each process on allproc
#ifdef PROCFS_ZOMBIE
* and zombproc.
#endif
*/
case Proot: {
#ifdef PROCFS_ZOMBIE
int doingzomb = 0;
#endif
int pcnt = 0;
struct proc *p;
ALLPROC_LOCK(AP_SHARED);
p = LIST_FIRST(&allproc);
for (; p && uio->uio_resid >= delen; i++, pcnt++) {
bzero((char *) dp, delen);
dp->d_reclen = delen;
switch (i) {
case 0: /* `.' */
case 1: /* `..' */
dp->d_fileno = PROCFS_FILENO(0, Proot);
dp->d_namlen = i + 1;
bcopy("..", dp->d_name, dp->d_namlen);
dp->d_name[i + 1] = '\0';
dp->d_type = DT_DIR;
break;
case 2:
dp->d_fileno = PROCFS_FILENO(0, Pcurproc);
dp->d_namlen = 7;
bcopy("curproc", dp->d_name, 8);
dp->d_type = DT_LNK;
break;
default:
while (pcnt < i) {
p = LIST_NEXT(p, p_list);
if (!p)
goto done;
if (p_can(curproc, p, P_CAN_SEE, NULL))
continue;
pcnt++;
}
while (p_can(curproc, p, P_CAN_SEE, NULL)) {
p = LIST_NEXT(p, p_list);
if (!p)
goto done;
}
dp->d_fileno = PROCFS_FILENO(p->p_pid, Pproc);
dp->d_namlen = sprintf(dp->d_name, "%ld",
(long)p->p_pid);
dp->d_type = DT_DIR;
p = LIST_NEXT(p, p_list);
break;
}
if ((error = uiomove((caddr_t)dp, delen, uio)) != 0)
break;
}
done:
#ifdef PROCFS_ZOMBIE
if (p == 0 && doingzomb == 0) {
doingzomb = 1;
p = zombproc.lh_first;
goto again;
}
#endif
ALLPROC_LOCK(AP_RELEASE);
break;
}
default:
error = ENOTDIR;
break;
}
uio->uio_offset = i * delen;
return (error);
}
/*
* readlink reads the link of `curproc' or `file'
*/
static int
procfs_readlink(ap)
struct vop_readlink_args *ap;
{
char buf[16]; /* should be enough */
struct proc *procp;
struct vnode *vp = ap->a_vp;
struct pfsnode *pfs = VTOPFS(vp);
char *fullpath, *freepath;
int error, len;
switch (pfs->pfs_type) {
case Pcurproc:
if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc))
return (EINVAL);
len = snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid);
return (uiomove(buf, len, ap->a_uio));
/*
* There _should_ be no way for an entire process to disappear
* from under us...
*/
case Pfile:
procp = PFIND(pfs->pfs_pid);
if (procp == NULL || procp->p_cred == NULL ||
procp->p_ucred == NULL) {
printf("procfs_readlink: pid %d disappeared\n",
pfs->pfs_pid);
return (uiomove("unknown", sizeof("unknown") - 1,
ap->a_uio));
}
error = textvp_fullpath(procp, &fullpath, &freepath);
if (error != 0)
return (uiomove("unknown", sizeof("unknown") - 1,
ap->a_uio));
error = uiomove(fullpath, strlen(fullpath), ap->a_uio);
free(freepath, M_TEMP);
return (error);
default:
return (EINVAL);
}
}
/*
* convert decimal ascii to pid_t
*/
static pid_t
atopid(b, len)
const char *b;
u_int len;
{
pid_t p = 0;
while (len--) {
char c = *b++;
if (c < '0' || c > '9')
return (NO_PID);
p = 10 * p + (c - '0');
if (p > PID_MAX)
return (NO_PID);
}
return (p);
}
/*
* procfs vnode operations.
*/
vop_t **procfs_vnodeop_p;
static struct vnodeopv_entry_desc procfs_vnodeop_entries[] = {
{ &vop_default_desc, (vop_t *) vop_defaultop },
{ &vop_access_desc, (vop_t *) procfs_access },
{ &vop_advlock_desc, (vop_t *) procfs_badop },
{ &vop_bmap_desc, (vop_t *) procfs_bmap },
{ &vop_close_desc, (vop_t *) procfs_close },
{ &vop_create_desc, (vop_t *) procfs_badop },
{ &vop_getattr_desc, (vop_t *) procfs_getattr },
{ &vop_link_desc, (vop_t *) procfs_badop },
{ &vop_lookup_desc, (vop_t *) procfs_lookup },
{ &vop_mkdir_desc, (vop_t *) procfs_badop },
{ &vop_mknod_desc, (vop_t *) procfs_badop },
{ &vop_open_desc, (vop_t *) procfs_open },
{ &vop_pathconf_desc, (vop_t *) vop_stdpathconf },
{ &vop_print_desc, (vop_t *) procfs_print },
{ &vop_read_desc, (vop_t *) procfs_rw },
{ &vop_readdir_desc, (vop_t *) procfs_readdir },
{ &vop_readlink_desc, (vop_t *) procfs_readlink },
{ &vop_reclaim_desc, (vop_t *) procfs_reclaim },
{ &vop_remove_desc, (vop_t *) procfs_badop },
{ &vop_rename_desc, (vop_t *) procfs_badop },
{ &vop_rmdir_desc, (vop_t *) procfs_badop },
{ &vop_setattr_desc, (vop_t *) procfs_setattr },
{ &vop_symlink_desc, (vop_t *) procfs_badop },
{ &vop_write_desc, (vop_t *) procfs_rw },
{ &vop_ioctl_desc, (vop_t *) procfs_ioctl },
{ NULL, NULL }
};
static struct vnodeopv_desc procfs_vnodeop_opv_desc =
{ &procfs_vnodeop_p, procfs_vnodeop_entries };
VNODEOP_SET(procfs_vnodeop_opv_desc);
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